Here’s what’s new, fixed, and broken in Windows 10 Mobile Build 14977

Microsoft today released Windows 10 Build 14977 to Insiders in the Fast Ring. The latest build is only available to Mobile devices, and it brings support for EPUB files on Edge, as well as the usual improvements and bug fixes.

What’s new

Read EPUB books in Microsoft Edge on your phone: In addition to being able to read any unprotected e-book in the EPUB file format on your PC with Microsoft Edge – you can also read unprotected e-book in the EPUB file format with Microsoft Edge on your phone! When you open an unprotected e-book in Microsoft Edge, you will be taken into a customizable reading experience where you can change the font and text size and choose between 3 themes: light, sepia, and dark. As you read, you can leave bookmarks. To navigate through an e-book, you can use the table of contents or seek bar at the bottom of the browser. And you can also search for words or phrases and use Cortana to define specific words.

What’s fixed

We’ve changed the rendering technology used for many types of UWP app content, so please provide feedback through the Feedback Hub if you notice any new visual glitches in UWP apps.

Alarms sent by 3rd party alarm apps will now break through Cortana’s Quiet Hours – we appreciate all the app developers who logged feedback requesting this, keep it coming!

We’ve removed the top-level option in Notification Settings to disable alarms on the lock screen – alarm reliability is a top priority for us, and we’ve found this setting was frequently enabled accidentally, without awareness that it would stop alarms from waking the phone when the phone was locked. For those who still wish to enable this setting, it’s will continue to be available under the per-app notification settings.

Notifications from Settings can now be customized or disabled – option is available under Settings > System > Notifications > Settings

We have enabled OAuth support for Yahoo Mail accounts. This will improve sync reliability for those accounts, and provide a secure experience while browsing your email.

We fixed an issue where disconnecting and reconnecting a wired headset while watching a video might result the audio no longer working.

We fixed an issue Insiders may have experienced where certain music apps would unexpectedly stop playing music after a single song.

We fixed an issue where closing a tab in Microsoft Edge, exiting the app, and then relaunching it would sometimes result in Edge opening to a blank page with the closed tab’s web address in the URL bar.

We fixed an issue where the Start Settings page wasn’t rendering when opened on external screen while using Continuum.

We’ve made a number of translation improvements, including, for French (France and Canada) speakers, fixing a grammatical error in the “Don’t Forget!” text seen when shutting down the phone so it now says “N’oubliez pas”, and for Chinese speakers, fixing an issue where the option to clear the Chinese Input Method Editor’s input history was displaying in English rather than Chinese. If you see any other translations that aren’t as you’d expect, please log feedback – we’re listening!

We fixed an issue where, if the setting to show notifications above lock had been turned off, booting the device and immediately checking the Action Center while the phone was locked could result in the Action Center not displaying any notifications after the phone had been unlocked.

We fixed an issue Insiders may have experienced where the Camera app might not appear after using the hardware camera button while the screen was off or while on the Glance screen.

We fixed an issue where Bangla (Bangladesh) keyboard text prediction might stop working after entering character followed by a vowel mark.

What’s broken

Please avoid attempting to install new languages, keyboards, and speech packs on your phone. There is a chance these downloads may get stuck and not finish downloading. If you have existing languages, keyboards, and speech packs installed – they will carry over when you update to new builds. You can use Windows Device Recovery Tool to go back to Windows Phone 8.1 or Windows 10 Mobile, install any languages, keyboards, and speech packs you need and then update to the latest build in the Fast ring as a workaround.

Windows 10 phones with 8GB of internal storage such as the Lumia 550 and 650 will likely receive an 0x800700b7 error when attempting to update to this build.